Patients with systemic lupus erythematosus (SLE) and the related antiphospholipid syndrome (APS) are predisposed to life-threatening thrombotic events. Neutrophils, and in particular neutrophil extracellular traps (NETs), have recently been linked to both active SLE and thrombosis. The possibility that NETs might be an important trigger of thrombosis in autoimmune disease patients has not, however, been rigorously evaluated. This award will play a critical role in helping me achieve my long-term career goals, which include: (1) becoming an expert in SLE and APS pathogenesis, especially the interplay between innate immune responses and thrombosis, (2) establishing a career as an independent investigator at a leading medical research institution, and (3) mentoring and fostering the development of trainees. These objectives will be reached by incorporating both a strong mentorship environment and a formal instructional plan. The plan focuses on specific scientific and career development goals. Mentorship Environment: I am currently a Clinical Lecturer in the Division of Rheumatology at the University of Michigan. I will become a tenure-track Assistant Professor on January 1, 2014. With this promotion, my time will be protected for research with just one-half day of clinic per week. Further, as is detailed in the Letter of Institutional Suppor, substantial start-up funds will be provided to support my research activities. Over the past two years, I have received strong training from Dr. Mariana Kaplan as an immunologist. In this proposal, I am seeking support for a significantly new research endeavor, as I turn my attention to the pathologic thrombosis inherent to systemic autoimmune diseases such as SLE. Dr. David Pinsky, an expert in cardiovascular medicine and the interplay between inflammation and thrombosis, will be my primary research mentor going forward. Formal Instruction: My scientific goals include: (1) applying models of neutrophil activation and thrombosis to the rheumatic diseases, (2) working effectively and efficiently with patient samples, and (3) mechanistically studying platelet signaling and activation. Basic science coursework will be through several centers at the University of Michigan including the Center for Statistical Consultation and Research, the Flow Cytometry Core, and the Center for Live Cell Imaging. I also plan to regularly attend the intensive Symposium on Hemostasis, held biennially in Chapel Hill, NC. Equally important are my career development goals, which include: (1) improving written and oral communication skills, (2) developing IRB proposals for research on human subjects, and (3) enriching my mentoring skills. Specific instructional programs and courses will be utilized including the Michigan Institute for Clinical and Health Research, IRBMED, the Program for Education and Evaluation in Responsible Research and Scholarship, and the Undergraduate Research Opportunity Program. Research: Globally, I plan to explore the hypothesis that exaggerated NET formation is an important mediator of pathologic thrombosis in SLE and APS patients. Aim 1 will study the role of antiphospholipid antibodies (the hallmark of APS, and also frequently found in SLE) in activating neutrophils to release NETs. Aim 2 will explore the extent to which SLE platelets interact with neutrophils to promote NET formation. Aim 3 will build on the human studies of Aims 1 and 2 by testing the importance of neutrophils and platelets in animal models of autoimmune-mediated thrombosis and vascular damage.